1. Field of the Invention
The present invention relates to determining whether a scanned original document is in color or monochrome. More specifically, the present invention relates to an image processing device and method that can handle a background color as monochrome even when the background color is chromatic, by extracting and masking the background color of the scanned original document.
2. Description of the Related Art
In order to determine whether a scanned original document is in color or monochrome, the conventional art suggests determining whether image data is in color or monochrome by dividing a predetermined area in a chromaticity plane (an a*b* plane of the L*a*b* uniform color space) into 25 rectangular areas, and determining whether or not a pixel exists in each of the areas.
In the conventional art, each of the 25 areas is disposed in the vicinity of the origin of the chromaticity plane. Therefore, a background color area that is disposed outside the 25 areas cannot be detected. Thus, in the conventional art, it may be difficult to detect a chromatic background color (chromaticity and hue). In other words, in a color original document, the background color area may be disposed away from the origin of the chromaticity plane, and it may be difficult to extract and mask the background color. Moreover, it is desirable to mask the background color by using a simple arithmetic circuit or arithmetic processing.